 Nikolayevsk-on-Amur was occupied in September 1918 by the Imperial Japanese Army as part of Japan's Siberian Intervention force.In early February 1920, the town had a Japanese civilian community of around 450 people, and a military garrison of 350 men from the Imperial Japanese Army's 14th Infantry Division.In addition to the Japanese presence, the Russian White Army housed a garrison of roughly 300 men.